diff --git a/__denotests__/mocks/hello.txt b/__denotests__/mocks/hello.txt
new file mode 100644
index 0000000..95d09f2
--- /dev/null
+++ b/__denotests__/mocks/hello.txt
@@ -0,0 +1 @@
+hello world
\ No newline at end of file
diff --git a/__denotests__/plugins/basic-integrity.test.js b/__denotests__/plugins/basic-integrity.test.js
index ce81405..1893f70 100644
--- a/__denotests__/plugins/basic-integrity.test.js
+++ b/__denotests__/plugins/basic-integrity.test.js
@@ -1,4 +1,9 @@
-import { assert } from "https://deno.land/std@0.167.0/testing/asserts.ts";
+import {
+    assert,
+    assertThrows,
+    assertRejects,
+    assertEquals
+} from "https://deno.land/std@0.167.0/testing/asserts.ts";
 
 Deno.test("plugin load", async () => {
     const bi = await import('../../plugins/basic-integrity/cli.js')
@@ -43,4 +48,46 @@ Deno.test("get-integrity action defaults", async () => {
     assert(gia.output.default == "json")
 });
 
-//TODO cont.
+Deno.test("get-integrity verifies arguments are sane", async () => {
+    const bi = await import('../../plugins/basic-integrity/cli.js')
+    const gi = bi.actions["get-integrity"]
+    assertRejects(gi.run, Error, "Expected non-empty list of files to generate digests of.")
+    assertRejects(async ()=>{
+        await gi.run(['no-such-file'])
+    }, Error, "No such file or directory")
+    assertRejects(async ()=>{
+        await gi.run(['irrelevant'], [])
+    }, Error, "Expected non-empty list of algorithms to use.")
+    assertRejects(async ()=>{
+        await gi.run(['irrelevant'], ['SHA-384'], false)
+    }, Error, "Expected either 'json' or 'text' as output type to generate.")
+});
+
+Deno.test("get-integrity handles paths in a sane way", async () => {
+    const bi = await import('../../plugins/basic-integrity/cli.js')
+    const gi = bi.actions["get-integrity"]
+    assertEquals(await gi.run(['./']), '{}')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt']), '{"./__denotests__/mocks/hello.txt":["sha256-uU0nuZNNPgilLlLX2n2r+sSE7+N6U4DukIj3rOLvzek="]}')
+    assertEquals(await gi.run(['./', './__denotests__/mocks/hello.txt']), '{"./__denotests__/mocks/hello.txt":["sha256-uU0nuZNNPgilLlLX2n2r+sSE7+N6U4DukIj3rOLvzek="]}')
+});
+
+Deno.test("get-integrity handles algos argument in a sane way", async () => {
+    const bi = await import('../../plugins/basic-integrity/cli.js')
+    const gi = bi.actions["get-integrity"]
+    assertRejects(async ()=>{
+        await gi.run(['./__denotests__/mocks/hello.txt'], ['BAD-ALG'])
+    }, Error, 'Unrecognized algorithm name')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-256']), '{"./__denotests__/mocks/hello.txt":["sha256-uU0nuZNNPgilLlLX2n2r+sSE7+N6U4DukIj3rOLvzek="]}')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-384']), '{"./__denotests__/mocks/hello.txt":["sha384-/b2OdaZ/KfcBpOBAOF4uI5hjA+oQI5IRr5B/y7g1eLPkF8txzmRu/QgZ3YwIjeG9"]}')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-512']), '{"./__denotests__/mocks/hello.txt":["sha512-MJ7MSJwS1utMxA9QyQLytNDtd+5RGnx6m808qG1M2G+YndNbxf9JlnDaNCVbRbDP2DDoH2Bdz33FVC6TrpzXbw=="]}')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-256', 'SHA-384', 'SHA-512']), '{"./__denotests__/mocks/hello.txt":["sha256-uU0nuZNNPgilLlLX2n2r+sSE7+N6U4DukIj3rOLvzek=","sha384-/b2OdaZ/KfcBpOBAOF4uI5hjA+oQI5IRr5B/y7g1eLPkF8txzmRu/QgZ3YwIjeG9","sha512-MJ7MSJwS1utMxA9QyQLytNDtd+5RGnx6m808qG1M2G+YndNbxf9JlnDaNCVbRbDP2DDoH2Bdz33FVC6TrpzXbw=="]}')
+});
+
+Deno.test("get-integrity handles output argument in a sane way", async () => {
+    const bi = await import('../../plugins/basic-integrity/cli.js')
+    const gi = bi.actions["get-integrity"]
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-256'], 'text'), './__denotests__/mocks/hello.txt: sha256-uU0nuZNNPgilLlLX2n2r+sSE7+N6U4DukIj3rOLvzek=\n')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-384'], 'text'), './__denotests__/mocks/hello.txt: sha384-/b2OdaZ/KfcBpOBAOF4uI5hjA+oQI5IRr5B/y7g1eLPkF8txzmRu/QgZ3YwIjeG9\n')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-512'], 'text'), './__denotests__/mocks/hello.txt: sha512-MJ7MSJwS1utMxA9QyQLytNDtd+5RGnx6m808qG1M2G+YndNbxf9JlnDaNCVbRbDP2DDoH2Bdz33FVC6TrpzXbw==\n')
+    assertEquals(await gi.run(['./__denotests__/mocks/hello.txt'], ['SHA-256', 'SHA-384', 'SHA-512'], 'text'), './__denotests__/mocks/hello.txt: sha256-uU0nuZNNPgilLlLX2n2r+sSE7+N6U4DukIj3rOLvzek= sha384-/b2OdaZ/KfcBpOBAOF4uI5hjA+oQI5IRr5B/y7g1eLPkF8txzmRu/QgZ3YwIjeG9 sha512-MJ7MSJwS1utMxA9QyQLytNDtd+5RGnx6m808qG1M2G+YndNbxf9JlnDaNCVbRbDP2DDoH2Bdz33FVC6TrpzXbw==\n')
+});